Calender and the like



Filed Jan. 4, 1951 y 18, 1954 c. F. scHNucK ET AL 2,678,465

CALENDER AND THE LIKE 4 Sheets-Sheet l May 18. 1-954 c. F. SCHNUCK ETAL 2,6

CALEND ER AND THE LIKE Filed Jan. 4, 19,51 4 Sheets-Sheet 2 5" .7. ,6? v 68 68 75 56 ea 73 7! 7o 70 I I I8 I 2 74 [410' as m.- G I Juventors attorney,

M ils, 1954 c. F. SCHNUCK ETAL 2,678,465

CALENDER AND THE LIKE Filed Jan. 4,1951 4 Sheets-Sheet s I 351.6 5| NW i. WMIIIIW@ Q M I nneEtora M y 8, 1954 c. F. scHNUcK 2% AL 2,678,465

CALENDER AND THE LIKE 4 Sheets-Sheet 4 Filed Jan. 4, 1951 I (Ittornegs Patented May 18, 1954 UNITED STATES PATENT DFFICE CALENDE'R AND THE :LIKE

Carl F. Schnuck, North Haven, and Emil H.

Johnson, Ansonia, Conn, 'a'ssignors to Farrel- Birmingham Company, Incorporated, Ansonia, 001111., a corporation of oonnecticut Application January 4, 1951, Serial No.204A4el 5 Claims. 1

This invention relates to a calender or likemachine in which plastic is passed through apair or pairs of cooperating rolls to issue therefrom in sheet form. The invention particularly involves means for effecting the proper adjustmentofsetting of the rolls to obtain a sheet or web of material of uniform thinness and of desired gauge.

In machinesof this character, relative adjustmentoi the cooperating rolls has been provided for in order to move one of the rolls toward or from the other to determine the gauge of the ,delivered sheet. At the present time, and particularly in connection with certain types of plastic material, there is a demand for very thin sheets or films, and this requires very heavy pressure upon the rolls considerably in excess of that which has been required for sheets or films of heavier gauge.

It has been the practice to provide adjusting screws which bear against the journal boxes in which the necks of therolls are mounted so that at least one of a cooperating pair of rolls may be urged against the other .by the adjustment of these screws. lhe heavy pressure required for the calenderingof very thin film results in such a great input of mechanical energy that some of this energy is convertedintoheat which flowsnot only into the rolls themselves but also into the journal boxes, adjusting screws, and even the housings. This, of course, effects a change the dimension of these parts due to expansion, and these changes will effect variations in the gaugeo'f the sheet'of material being delivered.

thinner the sheet f inaterialwhich issues from therolls, the. greater willbe thepercentage of error due to thisvariation resulting from distortion and expansion of the parts of the mill iromincrease in operating temperatures. At the present time, films are made as thin as from three thousandths tofive or six thousandths of an inch, and in the case of very thin gauges of this kind, a variation of one hali or one fourth of a thousandth in the gauge of thesheetlis undesirable.

In addition, when-very high pressures are-used on the adjusting .scrcws, this pressure will be further increased by expansion'of the .parts due to the generated heat, and there will be a danger of breakage of the: roll necks or destruction of the bearings due to this increased pressure. -Such-a hazard is also totbe avoided, and for this reasonit is desirable. that there be no increase in the pressure applied to the rolls above thatrequiredtto produce a sheet of the desired gauge. .If this pressure maybe maintained at this desired point, not only wlllthe delivered sheets be of the proper uniform gauge,lbut also [the hazard orbreakage oisonieypartoi the asunde -worse avdide'd.

According-to thepresent invention; it ispr posed to effect result b'ywhat may be termed hydraulic calendering. That is, a hydraulic mechanism is placed between the adjustingscrew and the journal box so that this screw, instead of actingdirectly upon the journal box, acts against the plunger of a hydraulic cylinder, the cylinder in turn being secured to the journal box so that the pressure applied to the rolls is that of the fluid in the cylinder. Therefore, the adjusting screw, instead of acting directly upon the journal box, as in prior constructions, acts upon the pressure in the cylinder, which in turn acts upon the journal cox, and if this fluid pressure is maintained at a uniform amount, the pressure upon the rolls will likewise be uniform regardless of expansion of the parts of the calender due to heat or other factors which might afiect this pressure it the adjusting screws acted directly upon the journal boxes.

It will, of course, be appreciated that arrangements other than that illustrated in the drawing may be employed provided that the pressure upon the cooperating rolls (or one of such rolls, as, in some instances, one of a pair of rolls is fixed) is applied through the hydraulic pressure, and means are provided for maintaining this pressure at the desired working level.

This fluid pressure in the cylinders may be controlled by means of pressure regulators and accumulators so that it will always be maintained at the desired amount. As pressure is applied to a working roll at each end thereof, it is some times desirable to maintain the hydraulic pressure at one end of the roll at a level difierent from that at the other end so that, if desired, a different pressure may be applied to one end of the roll than that applied at the other end.

In initiating the operation of the conventional calender, where the adjusting screw acts directly upon the roll bearings, the material is threaded into the roll bite with the rolls under working pressure but set to form a film of heavier gauge than that desired. The rolls are operating at a very slow speed and after the material hasbeen threaded in, the speed is slightly increased to effect thefgauging which is the adjustment of the rolls down to the final position which is done by the adjusting screws. While the speed is increased slightly during the gauging operation, it is not yet as high as the working speed so that after the gauging operationhas been completed, the machine is again speeded up for the calendering operation. This last increase in speed is 'efieotedafter the adjusting screws have been set in their final position, and it is the increase in temperature of the parts of the machinedue to this-increase in speedthat will affect the gauge of the material.

Moreover, the adjustmentsin the gauging operation may be very delicate, the movement of the rolls being at times much less than the thick ness of the delivered sheet, and in some instances, no more than one fourth of a thousandth of an inch. Where hydraulic pressure is employed, exact and close control over the pressure on the rolls may be maintained, and, likewise, compensation may be had for the distortion or expansion of the heavy machine parts due to heat developed during operation. 'Thus, once the gauging of the material is effected, it will be maintained at this gauge under the desired level of pressure even though the temperature of the machine parts increases due to increased speed of operation.

One object of the invention is to provide new and improved means for adjusting relative position of cooperating rolls in a calender or like machine.

A still further object of the invention is to provide means for maintaining the cooperating rolls in a calender or like machine in proper relative positions with respect to each other by hydraulic pressure.

A still further object of the invention is to provide a means for applying hydraulic pressure to at least one of a pair of cooperating rolls in a calender or like machine to hold such roll in proper position relatively to the cooperating roll so that a sheet of material of the desired uniform gauge may be produced and compensation made for increases in temperature of the parts of the calender when in operation.

Still another object of the invention is to provide at least one of a pair of cooperating rolls in a calender or like machine with an adjusting screw to apply pressure upon the rolls and hold them in proper relative positions, and to place a hydraulic cylinder between the adjusting screw and the roll journal so that the pressure of the screw will be transmitted to the roll by means of hydraulic pressure.

Still another object of the invention is to provide a novel method in adjusting the cooperating rolls of a calender or like machine to determine the thickness or the gauge of the sheet of material produced whereby said sheet will be of the desired and uniform thickness and the rolls will be under uniform pressure regardless of heat developed in the associated parts of the machine during its operation.

To these and other ends the invention consists in the novel features and combinations of parts to be hereinafter described and claimed.

In the accompanying drawings:

Fig. 1 is a side elevational view of a calender having our invention applied to one of the rolls thereof;

Fig. 2 is a front elevational view of the calender;

Fig. 3 is a sectional view on line 3-3 of Fig. 2;

Fig. 4 is an enlarged sectional View similar to Fig. 3 showing the hydraulic cylinder and associated parts;

Fig. 5 is a side elevational view of the parts shown in Fig. 4;

Fig. 6 is a detail view of a bearing plate used in connection with the device; and

Fig. '7 is a diagrammatic view showing conventional means for maintaining constant hydraulic pressure in the cylinders.

To illustrate a preferred embodiment of our invention, we have shown, in Fig. 1 of the drawings, a calender comprising a frame l8 and working rolls H, l2, l3 and I4. While, as shown, the

calender is of the Z-type, it will be understood that our improvements are not restricted to a calender of this form but may be employed in any apparatus where a relatively fine adjustment is required between two cooperating rolls.

As illustrated, our improvement is applied to the roll [4 to maintain this roll in proper relationship to its cooperating roll l3. For purposes of illustration it may be assumed that the roll it is fixed in position so far as movement in a horizontal direction is concerned, and, as will be described, the roll I4 is movable toward and from the roll it: so as to vary the degree of roll separation and, therefore, adjust these rolls to the proper position to produce a sheet of material of the desired gauge.-

It will also be understood that the frame includes the standards I5 and 16 (Fig. 2), one at each side of the machine, and that our hydraulic adjusting mechanism is carried by each of these standards, and is duplicated at each side of the machine so that pressure may be applied to each end of the roll I 4.

As shown in Fig. 3 of the drawings, the roll I4 is provided at each end with a reduced portion or neck i8 rotatably mounted in a journal box 19. This journal is mounted upon a wear plate which rests upon an adjusting nut 21 which will be described hereinafter. The wear plate 26 is slidably mounted upon this adjusting nut so that the wear plate together with the journal box may slide horizontally in the standard or frame. Also, at the top of the journal box is a similar wear plate 22 slidably engaging the underside of a cylinder 23, movably mounted in the standard It so that this wear plate will be free to move horizontally to the left, as shown in Fig. 3, and the cylinder may move vertically from the position shown in this figure.

Secured to the journal box 19 by bolts 24 is a support 25 which slidably rests upon ways 26 provided on the standard 16, and likewise, this support slidably engages ways 27 on the frame adjacent the upper end of the journal box. The bolts 24 pass through elongated openings in the support 25, as shown in Fig. 3, so as to permit relative movement of the journal box and the support in a vertical direction. This support carries a cylinder 28, shown in Fig. 3, which cylinder is provided with a head 29 in which is an opening 30 through which loosely passes the inner end of an adjusting screw 3|, this screw being threaded into the standard l6, as shown at 32 on Fig. 1.

This screw may be rotated by the conventional mechanism shown at 33, and it will be apparent that owing to its threaded connection with the frame, rotation of the screw will cause the end thereof to move toward, or be withdrawn from, the journal box l9. In the past, these adjusting screws have acted directly upon the journal boxes so as to move the roll with which they are associated directly toward and from its mating roll so as to adjust the degree of roll separation. In the present case, however, as will be explained below, we have mounted an hydraulic cylinder between the end of this adjusting screw and the journal box so that pressure of the adjusting screw is transmitted by hydraulic means to the journal box.

Referring to Fig. 4, it will be seen that cooperating wear plates 35 and 36 are provided in the journal box and cylinder respectively, and between these wear plates is a circular disk-like plate 31, provided with openings in which are a-ersaas disposed a plurality of bearing balls 38 so that the cylinder will act against the journal box I29 through the bearings 38. This permits the journal box to move vertically relatively to the cyllnder '28 if this is desired, :and, as will be hereinafter explained, means are provided to 'move theends of the roll M vertically in order torbring about a cross-axis relationship between this roll and the cooperating roll 13..

Within the cylinder is slidably disposed a cup-, shaped piston 4 0, and between the skirt portion of the piston :and the cylinder 11's is. suitable'packlng gland "Al to confine the pressure fluid to space '42 :betweentheiront end pf the .pistonand the end of the icylinder. Upon its end vrace the piston is provided with a projecting :guide rib 43 which moves in a 'slot M in the end of the cylinder. It will be noted that the space 42 is comparatively shallow as very little movement of the cylinder is required, the movement being only'enoughror very fine adjustments :of the rolls or to compensate for expansion of the :parts due to changes in temperature.

Theendof the adjusting :screw3l bears against the outer face oi the piston 46, as shown at '45, the piston being maintained against the screw by'theshydraulic :pressure within the chamber 42 of the cylinder. A :nut 46 is threaded upon the screw so that when the screw is backed ofi, this nut may engage the head 29 of the cylinder and draw the .journal boxto the left and draw the roll l liaway from the cooperating roll I3.

,It will-beseen 'by the above arrangement that the :roll .14 is held against, or in proper relationshipwith, theroll l3 :by the hydraulic pressure withinthe chamber 32, audit will be noted that it is desired 'to maintain the pressure in this chamber at thelamountdesiredfor the par ticular material which is being reduced to sheet form. Therefore, the fluid in the chamber 42 will always be at the rolling pressure desired, and, as this pressure is maintained at a constant level, the screw will always exert this pressure upon the journal box to maintain the two cooperating rolls in theirproper relationship.

.It is sometimes desired to maintain the axis of the .roll M at a slight angle with respect to the axis of the roll 1.3 instead of parallel therewithin order to compensate for the :bowing of the central portion of the rolls under extreme pressure, and provision has been made for moving each end of the roll 44 in .a vertical direction when this is desired. As shown in Fig. 3, the adjusting nut 21 is threadedly engaged by an adjusting screw at 48 rotatably mounted in thestandard l and rotated in a conventional manner by the gear 4d so that upon rotation of the screw 48, the adjusting nut 21 is moved upwardly or downwardly. The cylinder 23, which bears against the upper surface of the bearing plate 22 at th top of the journal box, receives therewithin the plunger or piston 50, fixed to a flangelil on the standard it, and provision may be made for admitting pressure hold to the chamber 52 of the cylinder so that when the 'journal box leis raised, it will be raised against fluid pressure Fin the chamber 52, and when the screw 48 is *backed off, this fluid pressure will tend to force the journal box downwardly.

It is "for the purpose of permitting this vertical movement of the ends of the roll I! that the bearing balls -38 "are provided between the wear plates 35 and 36, and the carrier plate 31., which supports the balls 38, is provided :upon its ends with itrunnionsrtlls vilszsh'o-wn in Figs. 4

and :5, each :ofrthe trunnions 54 is loosely received in an opening 55 a disk-like icradle member 56, this cradle member being provided with re-i cesses 51 and 5.8 which receive pins as and 60, the pin 59 being mounted upon the cylinder .28 while th pin 6i] is secured the journal box [9. Thus, when the journal box moves upwardly, for example, the right hand end .of the cradle '56., as shown in Fig. 5, will be moved upwardly, swinging about the pin 59 on the cylinder 28 so as to carry the carrier plate 31 upwardly approximately half the distance through which the journal box is raised. The provision of the carrier plate 31 and the bearing balls v3t thus provides .for easy adjustment of each of journal [boxes relatively to the associated cylinder 28., while "at the same time maintains a firm bearing of the cylinder upon the journal box so far as horizontal movement is concerned.

In .Fig. 7 of the drawing, we have shown in diagrammatic term means for admitting fluid pressure into the cylinders 28 (it is understood there will be one of these at each end of the roll M or other rolls which .are to 'be adjusted) and controlling the degree of pressure therein.

An air line is shown at 6 3 which may :lead to :a suitable source of air under pressure. .A threeway valve 54 connects this air line "to a T where the line is divided to lead to both of the cylinders. The branches of the T55 lead linto pressure regulators 6:3 by which the pressure is maintained at the desired figure in the pipes which lead from these regulators to ifourway valves 53. These valves control the admission of air under pressure to either end of the cylinders 59 through thelines wand H. Within each or the cylinders 69 is :a piston 12:50 that by means of the valve :68 the air pressure may be admitted to the cylinder upon either side 0f the piston to :move the latter in eitherdirection. It will be understood that the .pressureregulators 8.6 :may be adjusted to determine the degree of pressure existing in the cylinders 69 when the valves 68 .are in :position to admit air thereto.

- Gauges it may be provided to indicate the existing pressure to the operator.

:Each of the pistons 12 has :connected thereto a stem '14 extending into a cylinder "55 adapted to contain oil or other suitable ifluid. Each of the cylinders 15 is connected to one of the cylinders 28 by a pipe "it so that when air pressure is admitted to the cylinder 65 above the piston 12 the desired pressure will .be exerted by the stem M upon the fluid in the cylinder 15,:an'd likewise, of course, .upon the .fluid in thecyllnder 28. The pipes 16 may be connected through check valves 18 to a pipe 18 leading to a sump or supply of fluid 'so that if the oil in the circuit, including the cylinders 15 and '26, needs to be replenished, this may be done by raising the pistons :72 in the cylinders 63, and oil from the sump will be drawn into the @circuits through thecheck'valves i8. Gauges Ell may-beproride'd to indicate to the operator the pressure existingiin mach of the cylinders 28 and, as previously stated, it may be desirable in some instances to maintain a higher pressure in :one .cylindertha-n in the :other.

With the above construction :it will be seen that the air pressure in theacylinder 159 :above the pistons may the maintained at "a :desire'difiguma by adjustment cof the pressure regulators fit so that any desired pressure may obtain in the acylinder-s 2B which "will The the pressure diesirediior rolhng or sheeting the plastic :material which 7 is being run through the cooperating rolls. When this pressure has been regulated to the desired point during the gauging process pre viously described and the desired gauge of material has been reached during which time the rolls have been operating at a relatively slow speed, the speed may be increased to the working speed and no further adjustment will be necessary. Notwithstanding the fact that the increase of speed from the gauging speed to the working speed will cause an increase of temperature in the roll necks, the bearings and associated parts, compensation will be made for any expansion of these parts by an outward movement of the cylinder 23, thus creating a back pressure on the fluid in cylinders 75. This .back pressure will, however, be absorbed by the air under pressure in cylinder 69 so that the pressure against each end of the roll it will remain substantially constant. Thus an increase in temperature of the parts of the machine due to varying the speed of operation or to other causes will not afiect the gauge of the sheet of material which issues from the rolls.

While the invention has been illustrated as applied to a calender, it will be understood that it may be employed in any like machine such as a rubber refiner or other mill containing two or more, rolls where a fine adjustment of the pressure with which the rolls are held together is desired.

By the present invention an operator may hold to close rigid limits the rolling of a continuous uniform film of plastic material in gauged thickness of 3A of an inch or less, and this may be done with safe control against thermal deformation or enlargement of the roll bodies. In rolling films within this range of gauge, the material being rolled is in the nature of a lubricant between the roll surfaces, and films of this thinness are produced by dynamic pressure only. While the operation has been described as a calendering operation, as it is performed on a machine suitable for such work, herein de scribed combination of approaching the eventual gauge mechanically, and then finally applying hydraulic pressure for the exact gauge desired permits the production of films of a thinness which have hitherto been impractical.

While we have shown and described a preferred embodiment of our invention, it will be understood that it is not to be limited to all of the details shown, but is capable of modification and variation within the spirit of the inventionand within the scope of the claims.

What we claim is:

1. A calender or like apparatus comprising a pair of cooperating rolls, means for mounting said rolls for relative approaching and separating movements, means for applying pressure to one of said rolls, said means comprising a cylinder member and a piston member working in the cylinder, one of said members applying pressure to the roll, means to supply fluid pressure to said cylinder, and an adjusting screw to apply pressure to the other of said members, and means connecting said adjusting screw to said one memher to effect movement of the latter away from the roll by the screw.

2. A calender or like apparatus comprising a pair-of cooperating rolls, one of which is movable toward and from the other to adjust the amount of roll separation, frame means in which said rolls are rotatably mounted, means for applying pressure to the ends of the movable roll,

said means including a journal box at each end of the roll, a cylinder bearing against each of said journal boxes, a piston in each cylinder and adjusting screws in the frame against which the outer faces of the pistons bear, and means for introducing pressure fluid into said cylinders and means on said screws engaging a part on the cylinders to draw the latter away from the rolls.

3. A calender or like apparatus comprising a pair of cooperating rolls, one of which is movable toward and from the other to adjust the amount of roll separation, a frame in which said rolls are rotatably mounted, means for applying pressure to the ends of the movable roll, said means including a journal box at each end of the roll, a cylinder bearing against each of said journal boxes, a piston in each cylinder, abutments adjustably carried by the frame against which the outer faces of the pistons bear, means for introducing pressure fluid into said cylinders, means connecting said abutments to the cylinders to move the latter in a direction away from the rolls and regulating means for maintaining substantially constant pressure in each of said cylinders.

4. A calender or like apparatus comprising a pair of cooperating rolls, one of which is movable toward and from the other to adjust the amount of roll separation, a frame, journal boxes.

in which the ends of the movable roll are mounted, adjusting screws carried by the frame, hydraulic means disposed between the end or" each of said screws and one of the journal boxes to transmit pressure of said screws to the latter in the direction of the other roll, a plate mounted between the hydraulic means and the journal box, said plate carrying a plurality of pressure elements, and means supporting said plate for movement relatively to said journal box and said hydraulic means.

5. A calender or like apparatus comprising a pair of cooperating rolls, one of which is movable toward and from the other to adjust the amount of roll separation, a frame, journal boxes in which the ends of the movable roll are mounted, adjusting screws carried by the frame, hydraulic means disposed between the end of each of said screws and one of the journal boxes to transmit pressure of said screws to the latter in the direction of the other roll, a plate mounted between the hydraulic means and the journal box, said plate carrying a plurality of pressure elements, means supporting said plate for movement relatively to said journal box and said hydraulic means, said plate-supporting means comprising trunnions on opposite sides of said plate, a cradle member in which each of said trunnions is mounted, and each of said cradle members being pivoted to said journal box and said hydraulic means respectively.

References Cited in the his of this patent V UNITED STATES PATENTS Number Name Date 844,350 Hale Feb. 19, 1%? 1,500,679 Midgley July 8, 1924 1,672,118 Fraser June 5, 1928 1,980,882 See et a1 Nov. 13, 1934 2,034,939 Biggert, Jr. Mar. 24, 1936 FOREIGN PATENTS Number Country Date 501,883 Great Britain Mar. 7, 1939 528,671 Great Britain Nov. 4, 1940 

